package www.lagou.utils;

import com.alibaba.druid.pool.DruidDataSourceFactory;

import javax.sql.DataSource;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

public class DruidUtils {
    // 1.定义成员变量
    public static DataSource ds;

    // 2.静态代码块
    static {
        try {
            // 3.创建属性集对象
            Properties p = new Properties();

            // 4.加载配置文件（Druid 连接池不能主动加载配置文件，需要指定文件）
            InputStream inputStream = DruidUtils.class.getClassLoader().getResourceAsStream("druid.properties");

            // 5.Properties对象的load方法从字节流中读取配置信息
            p.load(inputStream);

            // 6.通过工厂类获取连接池对象
            ds = DruidDataSourceFactory.createDataSource(p);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // 获取连接的方法
    public static Connection getConnection() throws SQLException {
        return ds.getConnection();
    }

    //获取Druid连接池对象的方法
    public static DataSource getDataSource(){
        return ds;
    }

    // 5.释放资源/关闭连接的方法
    public static void close(Connection connection, Statement statement) {
        if (statement != null && connection != null) {
            try {
                statement.close();
                connection.close();
            } catch (SQLException throwables) {
                throwables.printStackTrace();
            }
        }
    }

    public static void close(Connection connection, Statement statement, ResultSet resultSet) {
        if (statement != null && connection != null && resultSet != null) {
            try {
                resultSet.close();
                statement.close();
                connection.close();
            } catch (SQLException throwables) {
                throwables.printStackTrace();
            }
        }
    }
}
